Shoes.com ship from inside the US, but they show the total cost at the Canadian checkout. Here is a quote from their shipping page:

Your order total with all shipping fees, custom fees, tariffs and taxes will be available during checkout in your chosen country and currency.

So you don't need to worry about any hidden fees - what you see at checkout will be all you have to pay. I did a test order, and Canadian shipping and duties add quite a bit on to the total cost.

So while this isn't the hottest deal in the world, if there is a specific pair of shoes or boots that you've been trying to get hold of, you could check the prices out there. At least the 15% coupon code helps offset those shipping and duties a little bit.